Hood hinge

ABSTRACT

A hinge base member (5) and a hinge upper member (15) of a hinge (1) for an engine hood (3) are provided with main bodies (5, 17) each having a laterally facing major plane, and link members (9, 10) are connected between the main bodies of the hinge base member and the hinge upper member and overlies the main bodies of the hinge base member and the hinge upper member from a first lateral side. The hinge upper member is provided with an extension (17) fixedly attached to the side part of the hood and extending forward from the main body of the hinge upper member with an offset to a second lateral side opposite to the first lateral side with respect to the main body of the hinge base member.

TECHNICAL FIELD

The present invention relates to a hood hinge based on a four-barlinkage mechanism, and in particular to a hood hinge suitable for use asa hinge for an engine hood of a motor vehicle.

BACKGROUND ART

An engine hood for a motor vehicle is often provided with a peripheryhaving a three dimensional configuration so as to conform to the profileof the adjacent part of the vehicle body for aesthetic reasons. In sucha case, it is necessary to make sure that no part of the hood hingeinterferes with the surrounding part of the vehicle body as the enginehood is opened and closed. JP2010-006315A discloses a hood hinge basedon a four-bar linkage mechanism. By using an engine hood using afour-bar linkage mechanism, the rotational center of the engine hood isallowed to move along a prescribed locus. According to this prior art,the hinge is configured such that the rear end of the hood moves upwardas the front end of the hood is raised so that the rear end of the hoodmay be prevented from interfering with the adjacent part of the vehiclebody.

JP2003-220973A discloses an engine hood provided with a pop-up actuatorfor lifting a rear end part of the engine hood at the time of a crashwith a pedestrian so that the impact load acting on the pedestrian maybe reduced by raising the rear end part of the engine hood.

Since the four-bar linkage mechanism is more complex than a simple hingehaving a fixed rotational center, various considerations are required indesigning the hinge. In particular, when incorporating a pop-up actuatorin the hood hinge, it is important to ensure an adequate downwarddeformation stroke to the hood hinge at the time of a crash with apedestrian.

In view of such a problem of the prior art, a primary object of thepresent invention is to provide a hood hinge incorporated with a pop-upactuator that can provide a large amount of downward stroke when thepop-up actuator is deployed.

To achieve such an object, the present invention provides a hood hinge(1) configured to pivotally support a rear end of a hood (3) covering afront part of a vehicle body (2) from above, the hinge including a hingebase member (5) fixedly attached to the vehicle body, a hinge uppermember (15) fixedly attached to a side part of the hood, and a pair oflink members (9, 10) each having a rearward slant and connected betweenthe hinge base member and the hinge upper member, wherein the hinge basemember and the hinge upper member are provided with main bodies (5, 17)each having a laterally facing major plane, the link members overlyingthe main bodies of the hinge base member and the hinge upper member froma first lateral side, and the hinge upper member is provided with anextension (17) fixedly attached to the side part of the hood andextending forward from the main body of the hinge upper member with anoffset to a second lateral side opposite to the first lateral side withrespect to the main body of the hinge base member.

Thereby, as the engine hood descends toward the engine room after theengine hood has been popped up at the time of a crash with a pedestrian,owing to the lateral offset between the extension of the hinge uppermember and the main body of the hinge base member, a relatively largedownward stroke is ensured to the hinge upper member without beinginterfered by the hinge base member so that the impact on the enginehood can be mitigated at the time of a crash.

Preferably, the extension of the hinge upper member is spaced laterallyfrom the main body of the hinge base member by a clearance as seen inplan view.

By defining the clearance between the extension of the hinge uppermember and the main body of the hinge base member, the interferencebetween these two parts can be positively ensured.

Preferably, the extension includes a plate member extending in a foreand aft direction continuously from the main body of the hinge uppermember and having a laterally facing major plane, and a flange (17 a)extending in the second lateral direction from an upper edge of theplate member, the flange being configured to be secured to the hood.

The extension can be provided with a high bending stiffness duringnormal operation owing an L-shaped cross section, and can provide afavorable support for the operation of the pop-up actuator at the timeof a crash with a pedestrian.

Preferably, an end of each link member on a side of the hinge uppermember is offset from another end of the link member on a side of thehinge base member to the first lateral side.

Thereby, the moment centered around the longitudinal axis (in the forean aft direction) and acting on the hinge during normal operation can beminimized.

Preferably, the hood hinge further comprises a pop-up actuatorconfigured to push up the flange of the extension of the hinge uppermember at a time of an emergency, and a readily deformable part isprovided in a boundary part between the main body and the extension ofthe hinge upper member.

The readily deformable part allows the force required to raise theextension and hence the rear end part of the hood to be minimized sothat the power output of the pop-up actuator is not required to beunduly great.

Preferably, a guide portion (7) is formed by bending a lower edge of themain body of the hinge base member to the first lateral side.

The guide portion may be configured to rest upon a corresponding part ofthe vehicle body when securing the hinge base member to the vehicle bodyso that the work in mounting the hinge base member to the vehicle bodyby using fasteners such as threaded bolts can be facilitated.

The present invention thus provides a hood hinge incorporated with apop-up actuator that can provide a large amount of downward stroke whenthe pop-up actuator is deployed.

BRIEF DESCRIPTION OF THE DRAWING(S)

FIG. 1 is a schematic side view showing an overall arrangement of a hoodhinge according to an embodiment of the present invention;

FIG. 2 is a perspective view of the hood hinge shown in FIG. 1;

FIG. 3 is a side view of the hood hinge;

FIG. 4A is a top view of the hood hinge;

FIG. 4B is a top view of the hood hinge including a fasteningarrangement thereof;

FIG. 5A is a side view of the hood hinge in a closed state;

FIG. 5B is a side view of the hood hinge in an open state; and

FIG. 6 is a fragmentary perspective view of the hood hinge and anassociated pop-up actuator.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

A preferred embodiment of the present invention is described in thefollowing with reference to the appended drawings.

FIG. 1 shows a front part of a vehicle body 2 according to an embodimentof the present invention. The vehicle body 2 defines an engine room inthe front part thereof to receive a power train and other devices. Theupper opening of the engine room is covered by an engine hood 3. Theengine hood 3 is composed of a hood frame 3 a, and a hood skin 3 boverlaid on the upper side of the hood frame 3 a and hemmed onto thehood frame 3 a along the outer periphery thereof. The hood frame 3 a andthe hood skin 3 b may be made of steel or aluminum alloy sheet metal, orcomposite material such as fiber reinforced plastic. The engine hood 3is inclined and curved so as to get gradually lower as it extendsforward and laterally outward, and conforms to the outer profile of thepart of the vehicle body 2 surrounding the engine hood 3.

The rear end of the engine hood 3 is supported by upper side members Bprovided on either side of the vehicle body 2 via a pair of hood hinges1, respectively. The hood hinges 1 allow the front end of the enginehood 3 to be lifted and lowered around a laterally extending rotationalcenter line.

Since the engine hood 3 and the hinges 1 are symmetric about a centrallongitudinal line, only the left hinge 1 is discussed in the followingto avoid redundancy. Referring to FIGS. 2 to 4, the hood hinge 1includes a hinge base member 5 fixedly attached to the upper side memberB of the vehicle body 2. The hinge base member 5 is made of a metallicplate member having a major plane facing sideways, and elongated in thefore and aft direction.

The hinge base member 5 is provided with a number of vertical foldinglines so as to form a pair of body mounting parts 5 a and a pair of linkmounting parts 5 b in an alternating manner in the fore and aftdirection. The body mounting parts 5 a extend along a plane parallel tothe major plane, and are each formed with a fastening hole 6 forreceiving a fastening bolt for securing the hinge base member 5 to thevehicle body 2, and a guide piece 7 projecting from the lower edge ofthe body mounting part 5 a and bent in the outboard direction. The frontend of the front body mounting parts 5 a is provided with a positioninghole 8 for positioning the hinge base member 5 with respect to thevehicle body 2 by fitting a corresponding projection (not shown in thedrawings) projecting from the vehicle body 2 into the positioning hole8. A similar positioning hole 8 is provided in an upper part of the rearpositioning hole 8 (FIG. 2).

The hinge base member 5 is configured to be attached to an upwardlyextending flange F of the upper side member B by aligning thepositioning holes 8 of the hinge base member 5 with the correspondingprojections of the vehicle body 2, and then passing fastening bolts Cthrough the respective fastening holes 6 so as to thread into respectivewelded nuts D welded to the flange F. In the illustrated embodiment, thehinge base member 5 is attached to the outboard side of the flange F.The guide pieces 7 extending from the body mounting part 5 a allow thehinge base member 5 to be properly positioned by abutting an opposingupper surface of the upper side member B of the vehicle body 2.

The link mounting parts 5 b also extend along a plane parallel to themajor plane, and are connected to lower ends of a first link member 13and a second link member 14 via pins 11 and 12, respectively. The lowerends of the two link members 13 and 14 are placed against the outboardside of the hinge base member 5. The two link members 13 and 14 extendupward and rearward, and are each provided with a rib for reinforcement.The two link members 13 and 14 are each appropriately bent at a suitablepart thereof as seen from sideways so as not to interfere with eachother as the two link members 13 and 14 perform the prescribed movementsthereof. Also, the upper parts of the two link members 13 and 14 areoffset from the lower parts thereof in the outboard direction inparallel with the lower parts of the respective link members 13 and 14.

The hood hinge 1 is further provided with a hinge upper member 15including a main body 16 having a major plane facing sideway andextending in the fore and aft direction. The upper edge of the main body16 is bent in the inboard direction so as to form a flange 16 a. Thehinge upper member 15 further includes an extension 17 continuouslyextending from the front end of the main body 16, and a flange 17 aextending continuously from the front end of the flange 16 a of the mainbody 16. The flange 17 a may also be considered as being bent from theupper edge of the extension 17, and as a part of the extension 17. Ascan be seen in FIG. 4A, the extension 17 is offset from the main body 16in the inboard direction, and the extension 17 and the main body 16 (theflange F of the upper side member B) extend substantially in the foreand aft direction parallel to each other. In particular, this offsetcreates a clearance S between the main body of the hinge base member 5(the flange F of the upper side member B) and the flange 17 a of theextension 17.

The flange 17 a of the extension 17 is provided with a pair of mountingholes 19, and is placed against the hood frame 3 a. The hinge uppermember 15 can be attached to the hood frame 3 a by passing the fasteningbolts C through the mounting holes 19 and threading the fastening boltsC into the welded nuts D welded to the hood frame 3 a. The pop-upactuator 4 is attached to a structural member of the vehicle body 2, andthe output end thereof opposes or abuts the flange 17 a of the extension17A. A notch 18 is provided in a boundary between the main body 16 andthe extension 17 to serve as a readily deformable part. In theillustrated embodiment, the notch 18 is provided between the main body16 of the hinge upper member 15 and the extension 17 (the main body ofthe extension 17).

The mode of operation of the hood hinge 1 of the illustrated embodimentis described in the following.

When the hood 3 is closed as shown in FIG. 5A, the two link members 9and 10 are positioned one above the other with a small gap definedtherebetween, and the extension 17 of the hinge upper member 15 isdisposed substantially horizontally. As the hood 3 is raised at thefront end thereof, the hinge upper member 15 is caused to tilt so thatthe front end thereof rises higher than the rear end thereof. At thesame time, the two link members 9 and 10 are raised upward at the rear(upper) ends thereof so that the hinge upper member 15 is raisedgenerally upward. Thus, owing to the action of the four-bar linkagemechanism formed by the hinge upper member 15, the two link members 9and 10, and the hinge base member 5, the hinge upper member 15 undergoesa rearward tilting movement and an upward and forward translationalmovement at the same time. As a result, the rear edge of the hood 3 isprevented from interfering with the adjacent part of the vehicle body 2.

The pop-up actuator 4 is configured to be activated upon detecting acrash with a pedestrian. The pop-up actuator 4 is incorporated with apyrotechnical device that drives a piston, and the output end connectedto the piston pushes up the hinge upper member 15, in particular theextension 17 thereof. The activation of the pop-up actuator 4 causes therear end of the hood 3 to be lifted by about 10 cm, and this creates astroke for plastic deformation of the hood 3 when an object collideswith or pushes onto the hood 3 so that the impact energy of the crashcan be converted into the deformation of the hood 3.

Upon activation of the pop-up actuator 4, the main body 16 of the hingeupper member 15 is pulled upward along an arcuate locus centered aroundthe front end of the hood 3 where the hood 3 is engaged by a hood latch(not shown in the drawings). The extension 17 follows the arcuatemovement of the rear end of the hood 3, but the main body 16 of thehinge upper member 15 is forced to move upward and rearward owing to theconstraint imposed thereon by the four-bar linkage mechanism. Accordingto the illustrated embodiment, owing to the presence of the notch 18(readily deformable part), the extension 17 can bend relative to themain body 16 at such a time so that the rear end of the hood 3 can beraised to a prescribed height, and the impact applied to an objectcrashing upon the hood 3 can be favorably mitigated. It also means thatthe power output of the pop-up actuator 4 is not required to be undulygreat.

When a downward force is applied to the hood hinge 1 at the time of acrash with an object such as a pedestrian, owing to the presence of thenotch 18 (readily deformable part), the extension 17 can bend relativeto the main body 16 so that the hood hinge 1 contributes to themitigation of impact on the object that has crashed onto the hood 3 andallows the hood 3 to be deformed in a favorable manner.

In the illustrated embodiment, the extension 17 of the hinge uppermember 15 is laterally offset from the main body of the hinge basemember 5 so as to define a clearance S therebetween in plan view.Therefore, when the hinge upper member 15 is pressed downward along withthe surrounding part of the hood 3 under the load of an object which hascrashed onto the hood 3, the extension 17 of the hinge upper member 15is prevented from interfering with the hinge base member 5 or any otherpart of the hinge 1 so that the hinge 1 along with the surrounding partof the hood 3 can deform in a downward direction without interferingwith other parts of the hinge 1 or the vehicle body. In other words, thehinge 1 of the illustrated embodiment allows the deformation stroke ofthe rear end part of the hood 3 at the time of a crash to be maximized,

In the hinge 1 of the illustrated embodiment, the two link members 9 and10 are each provided with bending lines in a middle part thereof so thatthe upper part of the link member is offset from the lower part thereofin the inboard direction. As a result, the moment applied to each linkmember 9, 10 with respect to the lateral direction during normaloperation of the hinge 1 can be minimized so that the bending loadacting on the link member can be minimized.

Although the present invention has been described in terms of apreferred embodiment thereof, the present invention is not limited bysuch an embodiment, but can be modified in a number of different wayswithout departing from the spirit of the present invention. Forinstance, the present invention is applicable even when the pop-upmechanism is absent. Also, the hood for which the hinge is used notlimited to an engine hood, but may be a trunk lid or any other lid forclosing a space in a vehicle.

The invention claimed is:
 1. A hood hinge configured to pivotallysupport a rear end of a hood covering a front part of a vehicle bodyfrom above, the hinge including a hinge base member fixedly attached tothe vehicle body, a hinge upper member fixedly attached to a side partof the hood, and a pair of link members each having a rearward slant andconnected between the hinge base member and the hinge upper member,wherein the hinge base member and the hinge upper member are providedwith main bodies each having a laterally facing major plane, the linkmembers overlying the main bodies of the hinge base member and the hingeupper member from an outboard side, and the hinge upper member isprovided with an extension fixedly attached to the side part of the hoodand extending forward from the main body of the hinge upper member withan offset to an inboard side with respect to the main body of the hingebase member, wherein an end of each link member on a side of the hingeupper member is offset from another end of the link member on a side ofthe hinge base member to the outboard side.
 2. The hood hinge accordingto claim 1, wherein the extension of the hinge upper member is spacedlaterally from the main body of the hinge base member by a clearance asseen in plan view.
 3. The hood hinge according to claim 1, wherein theextension includes a plate member extending in a fore and aft directioncontinuously from the main body of the hinge upper member and having alaterally facing major plane, and a flange extending toward the inboardside from an upper edge of the plate member, the flange being configuredto be secured to the hood.
 4. A hood hinge configured to pivotallysupport a rear end of a hood covering a front part of a vehicle bodyfrom above, the hinge including a hinge base member fixedly attached tothe vehicle body, a hinge upper member fixedly attached to a side partof the hood, and a pair of link members each having a rearward slant andconnected between the hinge base member and the hinge upper member,wherein the hinge base member and the hinge upper member are providedwith main bodies each having a laterally facing major plane, the linkmembers overlying the main bodies of the hinge base member and the hingeupper member from a first lateral side, and the hinge upper member isprovided with an extension fixedly attached to the side part of the hoodand extending forward from the main body of the hinge upper member withan offset to a second lateral side opposite to the first lateral sidewith respect to the main body of the hinge base member, wherein the hoodhinge further comprises a pop-up actuator configured to push up a flangeof the extension of the hinge upper member at a time of an emergency,and a readily deformable part is provided in a boundary part between themain body and the extension of the hinge upper member.
 5. A hood hingeconfigured to pivotally support a rear end of a hood covering a frontpart of a vehicle body from above, the hinge including a hinge basemember fixedly attached to the vehicle body, a hinge upper memberfixedly attached to a side part of the hood, and a pair of link memberseach having a rearward slant and connected between the hinge base memberand the hinge upper member, wherein the hinge base member and the hingeupper member are provided with main bodies each having a laterallyfacing major plane, the link members overlying the main bodies of thehinge base member and the hinge upper member from a first lateral side,and the hinge upper member is provided with an extension fixedlyattached to the side part of the hood and extending forward from themain body of the hinge upper member with an offset to a second lateralside opposite to the first lateral side with respect to the main body ofthe hinge base member, wherein a guide portion is formed by bending alower edge of the main body of the hinge base member to the firstlateral side.